Facebook Messenger is joining other messenger apps in their march for privacy by deploying full scale encryption in its chats, but it brings a few caveats to boot.

The social media platform started to implement end-to-end encryption to its 900 million Messenger users earlier this year. As it completed the rollout, Facebook announced the achievement on Oct. 4.

The feature puts privacy in the front row and can be enabled by each user as a "secret conversation." The option can be found in the top right of Messenger's "new message" screen, making the feature an opt-in.

In case you are wondering why the social media company would choose an opt-in model for end-to-end encryption, chances are that the tech does not want to interfere with the chatbots it announced in April.

Encryption will apply to photos, stickers and texts, but Facebook did not include GIFs and videos. What is more, group chats cannot tap into the feature, restricting its use to only one-on-one chats.

Facebook took a leaf out of Snapchat's playbook. In the secret conversation, the company embedded an ability that sets a timer on the chat. After the time expires, the conversation self-destructs. Users who want to tap into the new features of the Messenger app need to make sure that they rock the latest version, whether they are using iOS or Android.

No official information surfaced about the feature landing on Windows 10 Mobile.

Users who will text via Secret Conversations are looking at a full encryption of their messages, which will keep them protected from the privy eyes of hackers and/or government agencies.

It should be noted that Secret Conversations uses a reliable and highly commended encryption technique: the Signal protocol.

"Your messages are already secure, but with Secret Conversations they are encrypted from one device to another," the app informs users when they first use the feature.

Facebook also dabbled into encryption earlier this year, when it gifted its instant messaging app, WhatsApp, with end-to-end encryption.

Users of messaging apps voiced concern about their privacy, and the exposure of mass surveillance programs such as the ones deployed by the NSA made them even more aware of the dangers of having non-encrypted means of communication.

Reports about an upcoming end-to-end encryption to Facebook Messanger app landed earlier this year, and it is good to see the feature, which is already present in WhatsApp and iMessages, make its way into the main Facebook chat solution.